The effect of contact bounce of switches on the output of an electronic circuit has been a problem for a considerable time. Many types of electronic circuits have been invented for eliminating chatter in the output of an electronic circuit due to the contact bounce of input switches. Several circuits are disclosed in U.S. Pat. No. to Yukuo Kodama, U.S. Pat. No. 3,989,960, issued Nov. 2, 1976; to Izuhiko Nishimura, U.S. Pat. No. 4,057,738, issued Nov. 8, 1977; to Milton E. Hilliard, Jr., and Daniel J. Provine, U.S. Pat. No. 4,159,497, issued June 26, 1979; and to Borys Zuk, U.S. Pat. No. 4,185,210, issued Jan. 22, 1980.
The present invention is concerned with electronic circuit having a pair of switch means whose outputs are compared periodically upon the command of a clock signal so that upon a switch connected to the input of one of the switch means must reach a steady state operation with no contact bounce before the output of the comparison to coincide with the input signal is provided. Specifically, the invention is applicable with at least a pair of input signals to provide a binary code upon the operation of the switches in the input circuit. The output is provided after the contact bounce has terminated. The invention is even more applicable to a three input circuit which can generate eight functions of binary code where greater error can result for providing no change in the output until the input switches have returned to a stable state.